This invention relates to a color resolution compensator of a colored picture at a color television receiver, and more particularly to a color resolution compensator capable of reproducing a fine picture of a colored portion.
FIG. 1 is a block diagram of a part of a conventional color television receiver, in which an intermediate frequency signal is detected by a video detector 1 and given to a luminance signal amplifier 2 and a band pass amplifier 3. The band pass amplifier 3 picks up a carrier chrominance signal included in the composite color picture signal and supplies it to three color demodulators 4, 5 and 6.
The above-noted color demodulators 4, 5 and 6 demodulate the carrier chrominance signal to obtain three kinds of color-difference signals (R-Y, G-Y and B-Y) and supply them to three adders 7, 8 and 9.
The adders 7, 8 and 9 add the color-difference signal supplied to each adder with a luminance signal transferred from the luminance signal amplifier 2 to thereby produce three kinds of color primary signals and supply them to a picture tube 10.
The aforenoted conventional color television receiver generates a color-difference signal (e.g. an output of color demodulator 4) with a considerably narrower band width than that of the luminance signal transferred from luminance signal amplifier 2. For example, a NTSC system color television receiver has a frequency range of 0 Hz to 3 MHz for a luminance signal, while for a color difference signal has a narrow frequency range of no more than 500 KHz. Hence, in the colored picture, color-difference signals with a narrow bandwidth mainly constitute the picture, which is of poor sharpness and is dim.